A rash of fast-moving canine influenza across several eastern and central Minnesota counties has prompted the state Board of Animal Health to start tracking the spread of the virus.

Dr. Courtney Wheeler, a veterinarian with the state board, said seven dogs had tested positive for the virus as of Friday in Crow Wing, Kandiyohi, Ramsey, Sherburne and Wright counties, and the number of infected dogs is growing.

The board updates its website with information about new cases every time a dog tests positive for the flu.

Wheeler said it's important for dog owners to think about exposure to the virus and to not frequent places where it has been identified. She recommended calling a veterinarian immediately if owners see their dog show some symptoms, which include a cough, runny nose, sneezing, lethargy and fever.

The virus is transmitted through coughing, sneezing and direct contact between dogs or contaminated surfaces.

The board's website says the virus can occasionally be severe enough to result in pneumonia or death. No human infections of canine influenza have ever been reported.

Though it's rare, cats can also contract dog flu and should be kept away from infected dogs, the website said.

"Any county where it's been identified, the potential is there," Wheeler said. "If your pet is sick, you don't want to be responsible for the virus spreading to other parts of the state."

Hawk Creek Animal Shelter in Willmar recently began a three-week voluntary quarantine after vets there noticed sick dogs. Bobbie Bauman, director of the Humane Society of Kandiyohi and Meeker counties, said that while one dog tested positive for the flu in preliminary tests, confirmation tests showed that no dogs had the flu. Some, however, had canine distemper and mycoplasma pneumonia.

Bauman said the dogs that aren't sick will be bathed and put up for adoption in a separate area of the shelter.

Of the 27 dogs under quarantine, seven will "hopefully" be available this week, she said.

Bauman stressed that owners should take their dogs to the vet annually and make sure they are up to date on vaccinations to prevent the spread of diseases.

Dog flu was most recently put on the state board's official list of reportable diseases — those with the potential to negatively affect domestic species — in 2015.

In a board news release, state veterinarian Dr. Beth Thompson said dog flu was removed in June 2016 because it appeared to be diminishing.

But private practice veterinarians recently determined that "it's in everyone's best interest to place it back on the list."

This particular strain of influenza — H3N2 — was diagnosed in dogs in 10 central and southern U.S. states in May, according to the American Veterinary Medical Association (AVMA). The strain was first identified in dogs in Asia several years ago and was likely caused by a transfer of the avian flu virus. It made its way to the U.S. by 2015, when it was first reported in Chicago.

The AVMA said the mortality rate of canine influenza is less than 10 percent and occurs mainly in dogs with a severe form of the disease.

Sarah Jarvis • 612-673-4689